How to make faces face one direction
yes, there is. Set the pivot to individual elements instead of active element and scale them to zero along the desired axis.

There is a way to setup custom transform orientations if normal, view, global, local etc. does not offer the desired axis. I believe you can find it here further down the page.

https://www.blender.org/manual/editors/3dview/object/transform/transform_control/transform_orientations.html